Phylogeny and dating of divergences in N. pseudonarcissus L. using plastome sequences

Valeria Fochi ¹, Martino Adamo ¹, Virgile Noble ², Giuseppina Barberis ³, Marco Mucciarelli ¹

Dipartimento di Scienze della Vita e Biologia dei Sistemi, Università degli Studi di Torino, Torino, Italy. ¹, Conservatoire Botanique National Méditerranéen, Hyères, France. ², Dipartimento di Scienze della Terra, dell'Ambiente e della Vita, Università di Genova, Italy. ³

Narcissus pseudonarcissus L. (Amaryllidaceae) is a perennial geophyte native to Europe and distributed in different habitats, from grasslands to temperate nemoral forests. It is a species of great horticultural interest, but also an endangered and protected plant in the wild where it is threatened by loss of natural habitats. The species exhibits considerable morphological and genetic variation with numerous subspecies identified to date. For this study, a population of wild N. pseudonarcissus was sampled from a natural habitat in the Ligurian Alps at Monte Carmo di Loano (SV). This region at the boundary between the temperate alpine climate and the mild Mediterranean climate fosters a rich variety of plant species, many of which are endemic to the region. Currently, only two published chloroplast genomes are available for daffodils native to Europe: N. tazetta L. and N. poeticus L., the type species of the genus. Here, we report the complete chloroplast genome sequence of N. pseudonarcissus to address this and to identify new regions of genomic variability. Complete plastid genome was assembled from next-generation sequencing data obtaining a circular genome of 160,008 bp long assembly. It comprises a large single-copy region (108,400 bp), and a small single-copy region (16,434 bp), encoding 131 genes (87 protein coding genes, 37 tRNA genes and seven rRNA genes). Phylogeny run on currently available plastid genomes in Amaryllidaceae showed the monophyly of the genus within the subfamily Amaryllidoideae and the close relationship between N. pseudonarcissus and N. poeticus. Among the various subspecies of N. pseudonarcissus, the subspecies “provincialis” has long been recognized as a geographically isolated taxon native to the Alps of France. Nevertheless, the lack of a clear morphological delimitation has resulted in taxonomic ambiguity and its presence on the mountains of Italy remains undetermined. Given the ease with which Narcissus undergo spontaneous hybridization, even between distantly related species, having access to the plastid genome of N. pseudonarcissus represents an opportunity to further investigate the genetic basis of its variability at the wild state. Moreover, by integrating data from genetic analysis with flower morphometry and niche evolution we were able to demonstrate the genetic distinctiveness of two separate lineages currently found in the wild state in southern Alps and northern Apennines of Italy.

Main author career stage: Postdoc / Fellow

Contribution type: Poster

First choice session: 1. Systematics, phylogenetics, biogeography and evolution

Second choice session: 5. Genetics, genomics, and bioinformatics